[CrOS PhoneHub] Add BluetoothHelper::GetBluetoothPublicAddress()

Will be used to create a Bluetooth Classic connection via the Nearby
Connections library; required because we will not have access to the
full RemoteDeviceRef object when making the request (only the ID will be
available).

Bug: 1106937
Change-Id: I80ea9f180f95525cd8b679c3ac15eb418b1007c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2412839
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Auto-Submit: Kyle Horimoto <khorimoto@chromium.org>
Reviewed-by: James Vecore <vecore@google.com>
Cr-Commit-Position: refs/heads/master@{#807534}

chromeos/services/secure_channel/bluetooth_helper.h

@@ -22,6 +22,9 @@ namespace secure_channel {
 // Provides the ability to generate BLE advertisement service data and, given
 // service data that has been received in a BLE discovery session, identify the
 // device which sent the advertisement.
+//
+// Also provides functionality to retrieve the Bluetooth public address for a
+// device for use in Bluetooth Classic connections.
 class BluetoothHelper {
  public:
   virtual ~BluetoothHelper();
@@ -43,6 +46,10 @@ class BluetoothHelper {
       const std::string& service_data,
       const DeviceIdPairSet& device_id_pair_set);
 
+  // Note: An empty string is returned if there is no known public address.
+  virtual std::string GetBluetoothPublicAddress(
+      const std::string& device_id) = 0;
+
  protected:
   BluetoothHelper();
 

chromeos/services/secure_channel/bluetooth_helper_impl.cc

@@ -130,6 +130,16 @@ BluetoothHelperImpl::PerformIdentifyRemoteDevice(
   return base::nullopt;
 }
 
+std::string BluetoothHelperImpl::GetBluetoothPublicAddress(
+    const std::string& device_id) {
+  base::Optional<multidevice::RemoteDeviceRef> device =
+      remote_device_cache_->GetRemoteDevice(base::nullopt /* instance_id */,
+                                            device_id /* legacy_device_id */);
+  if (device)
+    return device->bluetooth_public_address();
+  return std::string();
+}
+
 base::Optional<BluetoothHelper::DeviceWithBackgroundBool>
 BluetoothHelperImpl::PerformIdentifyRemoteDevice(
     const std::string& service_data,

chromeos/services/secure_channel/bluetooth_helper_impl.h

@@ -57,6 +57,7 @@ class BluetoothHelperImpl : public BluetoothHelper {
   base::Optional<DeviceWithBackgroundBool> PerformIdentifyRemoteDevice(
       const std::string& service_data,
       const DeviceIdPairSet& device_id_pair_set) override;
+  std::string GetBluetoothPublicAddress(const std::string& device_id) override;
 
   base::Optional<BluetoothHelper::DeviceWithBackgroundBool>
   PerformIdentifyRemoteDevice(

chromeos/services/secure_channel/bluetooth_helper_impl_unittest.cc

@@ -83,6 +83,7 @@ multidevice::RemoteDeviceRef CreateLocalDevice(int id) {
       .SetInstanceId("local instance id " + base::NumberToString(id))
       .SetPublicKey("local public key " + base::NumberToString(id))
       .SetBeaconSeeds(CreateFakeBeaconSeeds(id))
+      .SetBluetoothPublicAddress(base::NumberToString(id))
       .Build();
 }
 
@@ -304,6 +305,12 @@ TEST_F(SecureChannelBluetoothHelperImplTest,
   EXPECT_FALSE(device_with_background_bool);
 }
 
+TEST_F(SecureChannelBluetoothHelperImplTest, BluetoothPublicAddress) {
+  EXPECT_EQ("1", test_local_device_1_.bluetooth_public_address());
+  EXPECT_EQ("1", helper_->GetBluetoothPublicAddress(
+                     test_local_device_1_.GetDeviceId()));
+}
+
 }  // namespace secure_channel
 
 }  // namespace chromeos

chromeos/services/secure_channel/fake_bluetooth_helper.cc

@@ -34,6 +34,13 @@ void FakeBluetoothHelper::SetIdentifiedDevice(
                                               is_background_advertisement)});
 }
 
+void FakeBluetoothHelper::SetBluetoothPublicAddress(
+    const std::string& device_id,
+    const std::string& bluetooth_public_address) {
+  device_id_to_bluetooth_public_address_map_[device_id] =
+      bluetooth_public_address;
+}
+
 std::unique_ptr<DataWithTimestamp>
 FakeBluetoothHelper::GenerateForegroundAdvertisement(
     const DeviceIdPair& device_id_pair) {
@@ -56,6 +63,11 @@ FakeBluetoothHelper::PerformIdentifyRemoteDevice(
   return service_data_to_device_with_background_bool_map_.at(service_data);
 }
 
+std::string FakeBluetoothHelper::GetBluetoothPublicAddress(
+    const std::string& device_id) {
+  return device_id_to_bluetooth_public_address_map_[device_id];
+}
+
 }  // namespace secure_channel
 
 }  // namespace chromeos

chromeos/services/secure_channel/fake_bluetooth_helper.h

@@ -37,6 +37,10 @@ class FakeBluetoothHelper : public BluetoothHelper {
                            multidevice::RemoteDeviceRef identified_device,
                            bool is_background_advertisement);
 
+  // Sets the data to be returned by a GetBluetoothPublicAddress() call.
+  void SetBluetoothPublicAddress(const std::string& device_id,
+                                 const std::string& bluetooth_public_address);
+
  private:
   // BluetoothHelper:
   std::unique_ptr<DataWithTimestamp> GenerateForegroundAdvertisement(
@@ -44,6 +48,7 @@ class FakeBluetoothHelper : public BluetoothHelper {
   base::Optional<DeviceWithBackgroundBool> PerformIdentifyRemoteDevice(
       const std::string& service_data,
       const DeviceIdPairSet& device_id_pair_set) override;
+  std::string GetBluetoothPublicAddress(const std::string& device_id) override;
 
   std::unordered_map<DeviceIdPair, DataWithTimestamp, DeviceIdPairHash>
       device_id_pair_to_service_data_map_;
@@ -51,6 +56,9 @@ class FakeBluetoothHelper : public BluetoothHelper {
   std::unordered_map<std::string, DeviceWithBackgroundBool>
       service_data_to_device_with_background_bool_map_;
 
+  std::unordered_map<std::string, std::string>
+      device_id_to_bluetooth_public_address_map_;
+
   DISALLOW_COPY_AND_ASSIGN(FakeBluetoothHelper);
 };